Particle simulation is one of fundamental simulation techniques and used for simulation of basic substances such as fluids or solids, as well as industrially important substances such as soils and powders, and biologically and medically important substances such as proteins. The applications include, for example, simulations of disasters such as landslides, liquefaction, and tsunamis, and drug discovery simulations such as protein design. Those various substance simulations are extremely valuable in application, and the progress of simulation techniques is important to promptly develop the applications.
A particle simulation embodies the movement of the entire particle group by storing the positions and velocities of individual particles as variables and tracking their changes based on a model. In particular, in the methods widely used as particle simulations, such as discrete element method (DEM) (clods, sands), smoothed particle hydrodynamics (SPH) (fluids), and molecular dynamics (MD) (molecules, proteins), the interactions between particles are simulated, and specifically the interactions are assumed to be symmetric (action-reaction law). Non-Patent Literature 1 below proposes an approach that accelerates a particle simulation using this symmetry. This approach is created for graphics processing unit (GPU) calculation so as to enable parallel calculation. In this approach, the use of symmetry is characterized in that a list of interaction pairs between particles, called a pair list, is created and used. The calculation of interactions based on this pair list reduces the entire simulation time.